I believe these are threads for kumihimo braiding. I received them as a gift, so I don't know the details, but the threads other than the gold one have been opened. The weight of the threads including the bags are as follows: White: 13.0g Red: 23.0g Light Blue: 26.5g Gold: 34.0g These belonged to my grandmother, who was a kumihimo instructor. Although the labels are missing, I believe the unlabeled threads are also silk. Please note that these items have been stored for a long time, so there may be yellowing or stains on the tape. I'll do my best to answer any questions you may have. Please feel free to contact me.